Dev null permission denied

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Its commonly reported that when users chroot into an existing linux environment on their harddrive, they encounter the /dev/null: Permission Denied error message. This page attempts to explain it and how to avoid it.

The error is caused by mounting a filesystem with the "nodev" mount option and then chrooting into it. Knoppix automatically places a "users" mount option into the /etc/fstab file, which implies this "nodev" option. This can happen if you save your Knoppix configure data to the same partition that you are using here, AND if you start with Knoppix with knoppix home=scan.

You can override this option by editting /etc/fstab and appending ",dev" to the options column or simply mount your new chroot filesystem by bypassing the /etc/fstab entirely by typing the following command:

mount -o remount,dev /dev/hda1

If the /dev/null warnings persist then before the chroot do :

mkdir /mnt/hda1/knx/source/KNOPPIX/KNOPPIX
mount --bind /KNOPPIX /mnt/hda1/knx/source/KNOPPIX
mount --bind /dev /mnt/hda1/knx/source/KNOPPIX/dev

And re-enter the chroot. Remember that you have to

umount /mnt/hda1/knx/source/KNOPPIX/dev
umount /mnt/hda1/knx/source/KNOPPIX
rmdir /mnt/hda1/knx/source/KNOPPIX/KNOPPIX

before building the CD image or your /dev directory on the CD will be messed up!